Perhaps all public restrooms should be mandated to consist of the following:
One working toilet
One working sink
Toilet paper
A hand drier or paper product for drying hands
A waste basket
A lidded depository for hygiene products
A lockable door
All unisex and all within a 100% enclosed space
Problem solved. Sure there will be opposition, the most important from an economic standpoint due to cost of implementation which is why such a mandate should allow a decade for compliance.
Beyond that their will be opposition from other sources, which I suspect will not garner much support:
The urinal lobby
The urinal cake lobby
The lobby that supports making other lives miserable for no discernible reason (likely the greatest source of remaining opposition)
The closeted gay Republican/religious leader lobby, which often solicits anonymous casual encounters in public restrooms right after that 'family values' speech.
Until full implementation, just let everyone use the restroom of the gender they identify with.
Read not to contradict and confute, not to believe and take for granted, not to find talk and discourse, but to weigh and consider. - Francis Bacon